Does the Lumbar Paraspinal Muscle Status Have a Role in Predicting Mechanical Complications After Adult Spinal Deformity Surgery?

Study designRetrospective analysis.ObjectivesTo assess the role of paraspinal muscle morphology in predicting complications after adult spinal deformity (ASD) surgery.Materials and MethodsA total of 93 patients who underwent surgery for ASD from 2017 to 2022 were enrolled. Using early postoperative X-ray, they were divided into proportioned (P), moderately proportioned (MP), and severely proportioned (DP) groups based on the Global Alignment and Proportion (GAP) scores. Further, they were classified into two groups: Group A (presence of mechanical complications) and Group B (no mechanical complications). In addition, other parameters including preoperative BMI, smoking status, cross-sectional area (CSA), and grades of paraspinal muscle fatty infiltration (FI) were calculated in all patients using preoperative MRI. These parameters were compared across the groups using a one-way analysis of variance (ANOVA). Post-hoc pairwise testing was done using Bonferroni's method. These were also compared between groups A and B using a 2-sample t-test.ResultsThe mean follow-up period was 32.7 months (24-64 months). 27 (29%) of 93 patients developed mechanical complications following ASD surgery. Of the 27 patients, 6 (22.2%) were proportioned, 10 (37%) were from MP and 11 (40.7%) were from the DP group. Group A had low CSA (<i>P</i> = 0.014), and high FI (<i>P</i> = 0.003) grades compared to group B. Further, 22.2% (6/27) had a history of smoking before surgery (OR = 6.57).ConclusionsWe recommend consideration of preoperative smoking, CSA, and FI of paraspinal muscles in addition to the GAP score to minimize mechanical complications in patients undergoing ASD surgery.